Vehicle detection and response

Abstract

A computer is programmed to identify a target vehicle to be monitored and to identify first and second virtual boundaries on a roadway based on a position of the target vehicle. The computer is further programmed to determine a first constraint value based on (1) a first boundary approach velocity and (2) a first boundary approach acceleration and a second constraint value based on (1) a second boundary approach velocity and (2) a second boundary approach acceleration. The computer is further programmed to identify a maneuver of the target vehicle based on whether the first and second constraint values violate respective thresholds or a position of the target vehicle relative to the first and second virtual boundaries violates a threshold and to adjust a path of a host vehicle according to the identified maneuver.

What is claimed is: 
     
       1. A system, comprising a computer including a processor and a memory, the memory storing instructions executable by the processor to:
 identify a target vehicle to be monitored; 
 identify first and second virtual boundaries on a roadway based on a position of the target vehicle; 
 determine a first constraint value based on (1) a first boundary approach velocity of the target vehicle including a heading angle of the target vehicle and (2) a first boundary approach acceleration of the target vehicle including a steering angle of the target vehicle; 
 determine a second constraint value based on (1) a second boundary approach velocity of the target vehicle including the heading angle of the target vehicle and (2) a second boundary approach acceleration of the target vehicle including the steering angle of the target vehicle; 
 identify a maneuver of the target vehicle based on whether the first constraint value violates a first threshold, the second constraint value violates a second threshold, or a position of the target vehicle relative to the first and second virtual boundaries violates a third threshold; and 
 adjust a path of a host vehicle to avoid the target vehicle according to the identified maneuver. 
 
     
     
       2. The system of  claim 1 , wherein the instructions further include instructions to identify the maneuver as a left turn when the first constraint value does not violate the first threshold, the second constraint value violates the second threshold, and the position of the target vehicle relative to the first virtual boundary does not violate the third threshold. 
     
     
       3. The system of  claim 1 , wherein the instructions further include instructions to identify the maneuver as a right turn when the first constraint value violates the first threshold, the second constraint value does not violate the second threshold, and the position of the target vehicle relative to the second virtual boundary does not violate the third threshold. 
     
     
       4. The system of  claim 1 , wherein the instructions further include instructions to input the identified maneuver into a path planning algorithm to generate an adjusted path to avoid the target vehicle. 
     
     
       5. The system of  claim 4 , wherein the instructions further include instructions to actuate one or more of a propulsion, a steering, or a brake of the host vehicle to follow the adjusted path to avoid the target vehicle. 
     
     
       6. The system of  claim 1 , wherein the instructions further include instructions to determine that the first value violates the first threshold based on a sign of the first value. 
     
     
       7. The system of  claim 1 , wherein the instructions further include instructions to determine that the position of the target vehicle violates the third threshold when the target vehicle crosses one of the first virtual boundary or the second virtual boundary. 
     
     
       8. The system of  claim 1 , wherein the instructions further include instructions to input a plurality of reference trajectories into respective equations defining the first and second virtual boundaries and the first and second constraint values, the equations including a plurality of reference coefficients, to minimize a cost function to generate a plurality of coefficients for the equations. 
     
     
       9. The system of  claim 8 , wherein the instructions further include instructions to predict an initiation time for a specified maneuver of one of the reference trajectories and to determine a time difference between the predicted initiation time and a specified initiation time for the specified maneuver. 
     
     
       10. The system of  claim 9 , wherein the instructions further include instructions to adjust the plurality of coefficients to minimize respective time differences for each of the plurality of reference trajectories. 
     
     
       11. The system of  claim 10 , wherein the instructions further include instructions to, upon minimizing a sum of the time differences, identify the plurality of coefficients associated with the minimized sum and assign the plurality of coefficients to replace the reference coefficients of the equations. 
     
     
       12. The system of  claim 8 , wherein the plurality of coefficients include a coefficient for the first boundary approach velocity and a second coefficient for the second boundary approach velocity. 
     
     
       13. A method, comprising:
 identifying a target vehicle to be monitored; 
 identifying first and second virtual boundaries on a roadway based on a position of the target vehicle; 
 determining a first constraint value based on (1) a first boundary approach velocity of the target vehicle including a heading angle of the target vehicle and (2) a first boundary approach acceleration of the target vehicle including a steering angle of the target vehicle; 
 determining a second constraint value based on (1) a second boundary approach velocity of the target vehicle including the heading angle of the target vehicle and (2) a second boundary approach acceleration of the target vehicle including the steering angle of the target vehicle; 
 identifying a maneuver of the target vehicle based on whether the first constraint value violates a first threshold, the second constraint value violates a second threshold, or a position of the target vehicle relative to the first and second virtual boundaries violates a third threshold; and 
 adjusting a path of a host vehicle to avoid the target vehicle according to the identified maneuver. 
 
     
     
       14. The method of  claim 13 , further comprising identifying the maneuver as a left turn when the first constraint value does not violate the first threshold, the second constraint value violates the second threshold, and the position of the target vehicle relative to the first virtual boundary does not violate the third threshold. 
     
     
       15. The method of  claim 13 , further comprising identifying the maneuver as a right turn when the first constraint value violates the first threshold, the second constraint value does not violate the second threshold, and the position of the target vehicle relative to the second virtual boundary does not violate the third threshold. 
     
     
       16. The method of  claim 13 , further comprising inputting the identified maneuver into a path planning algorithm to generate an adjusted path to avoid the target vehicle. 
     
     
       17. A system, comprising:
 a host vehicle including a propulsion, a brake, and a steering; 
 a target vehicle; 
 means for identifying first and second virtual boundaries on a roadway based on a position of the target vehicle; 
 means for determining a first constraint value based on (1) a first boundary approach velocity of the target vehicle including a heading angle of the target vehicle and (2) a first boundary approach acceleration of the target vehicle including a steering angle of the target vehicle; 
 means for determining a second constraint value based on (1) a second boundary approach velocity of the target vehicle including the heading angle of the target vehicle and (2) a second boundary approach acceleration of the target vehicle including the steering angle of the target vehicle; 
 means for identifying a maneuver of the target vehicle based on whether the first constraint value violates a first threshold, the second constraint value violates a second threshold, or a position of the target vehicle relative to the first and second virtual boundaries violates a third threshold; and 
 means for actuating at least one of the propulsion, the brake, or the steering of the host vehicle to avoid the target vehicle according to the identified maneuver. 
 
     
     
       18. The system of  claim 17 , further comprising means for identifying the maneuver as a left turn when the first constraint value does not violate the first threshold, the second constraint value violates the second threshold, and the position of the target vehicle relative to the first virtual boundary does not violate the third threshold. 
     
     
       19. The system of  claim 17 , further comprising means for identifying the maneuver as a right turn when the first constraint value violates the first threshold, the second constraint value does not violate the second threshold, and the position of the target vehicle relative to the second virtual boundary does not violate the third threshold. 
     
     
       20. The system of  claim 17 , further comprising means for inputting the identified maneuver into a path planning algorithm to generate an adjusted path to avoid the target vehicle.